Research and analysis

Biological techniques of still water quality assessment phase 3: method development

The development of a biological assessment method for assessing the quality of still waters of canals, lakes, temporary waters, ditches, brackish lagoons and ponds.


Biological Techniques of Still Water Quality Assessment - Phase 3. Method Development

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The aim of this project was to develop a biological method for assessing the quality of still waters (ponds, lakes, canals, temporary waters, ditches and brackish lagoons) in England and Wales. This report summarises the results of the third and final phase of the project.

In Phase 1, the project’s multimetric methodological approach was defined and the preferred biotic assemblages to be used for assessment identified (macrophytes, macroinvertebrates, diatoms and fish). As the range of work required for complete development of the method was extensive a multi-track approach was adopted to method development which could simultaneously progress significant sections of the project at different rates.

In Phase 2 initial development and testing of the method were undertaken in ponds and canals, in a trial area covering 30% of England and Wales, using two of the preferred assemblages (macroinvertebrates and macrophytes) (‘Track 1’). The use of diatom and fish assemblaes in multimetric assessment was evaluated (‘Track 2’) and a desk-study of diagnostic methods for identifying the causes of environmental degradation was undertaken (‘Track 3’).

In Phase 3 the assessment method for canals and small lentic waterbodies (ponds and lakes up to 5 ha) was extended to cover the whole of England and Wales.

Published 1 January 2000